L-苯丙氨酸聚肽的酶催化合成

聚肽是由人工合成的氨基酸聚合物,具有良好的生物相容性和生物可降解性。本文以菠萝蛋白酶为催化剂,在温和条件下于非水体系中从L-苯丙氨酸甲酯聚合得到齐聚L-苯丙氨酸。通过FT-IR、~1HNMR、MS和MALDI-TOF确定了齐聚L-苯丙氨酸的结构和聚合度。通过单因素考察了菠萝蛋白酶催化聚合反应的最优条件。结果表明,在40℃下用2.44U菠萝蛋白酶于15%DMSO的磷酸缓冲液(pH=8.0)中催化0.43g L-苯丙氨酸甲酯盐酸盐聚合,反应3h后齐聚L-苯丙氨酸得率达到最大值,为35.67%。

Enzymatic Synthesis of L-phenylalanine Polypeptide

Artificial polymers of amino acids, polypeptides, show the advantages of biocompatibility and biodegradability. In this study, the oligo-L-phenylalanine was prepared by the polymerization reaction of bromelain from L- phenylalanine methyl ester in the non-aqueous media under the mild conditions. The structure and polymerization degree of the oligo-L-phenylalanine were elucidated by FT-IR, 1H-NMR, MS and MALDI-TOF. The characterizations indicated the product is oligo-L-phenylalanine with a maximal polymerization degree of eight. Finally, the optimum polymerization conditions were evaluated through single-factor approach. The highest value of yield, 35.67%, could be achieved when 0.43 g L-phenylalanine methyl ester hydrochloride in 15% DMSO phosphate buffer (pH=8.0) was polymerized by 2.44 U bromelain at 40 °C for 3 hours.